理解生物体系光致电子转移机理对于人们将光能有效转化为化学能有重要意义。在蛋白质中，光致电子转移反应与反应位点溶剂分子涨落弛豫可能会产生一定的耦合，这种动力学效应一般用Sumi-Marcus二维理论模型进行描述。近年来在氧化态的黄素氧化还原蛋白中发现超快时间尺度（<1ps）的电子转移反应，此时体系对应着Sumi-Marcus二维理论模型中的冷冻区，但实验得到的反应物衰减动力学与现有的Sumi-Marcus二维理论模型存在矛盾的地方。我们计划使用温度调控的手段，结合分子生物学和超快光谱学技术，解析黄素氧化还原蛋白体系冷冻区超快时间尺度的电子转移反应机理。本项目的开展致力于从分子层面上理解蛋白机器如何有效利用光能，对于未来设计合成更高效的人工体系具有启发意义。

Understanding the mechanism of biological photo-induced electron transfer is key to realizing the transformation from solar energy to chemical energy. In some proteins, photo-induced electron transfer is coupled with dielectric relaxation of the solvent molecules in the reaction site and such dynamical effects have been described by Sumi-Marcus two-dimensional model. Recent years have observed that the short-range electron transfer occurs in the ultrafast time region (<1ps) in flavodoxin with oxidized flavin, which corresponds to the frozen region in the Sumi-Marcus two-dimensional model. With the approach of temperature modulation, we propose to combine molecular biology and ultrafast spectroscopy to elucidate the mechanism of ultrafast electron transfer in the frozen region. Experimental results from different species will be compared and interpreted according to the X-ray crystal structures. This proposal is aimed to understand how protein machines effectively utilize solar energy from the molecular level and to shed light on designing more advanced artificial systems in the future.